EP 0465028 A2 19920108 - Document sensing apparatus.
Title (en)
Document sensing apparatus.
Title (de)
Vorrichtung zum Erkennen von Dokumenten.
Title (fr)
Dispositif pour détecter des documents.
Publication
Application
Priority
GB 9014407 A 19900628
Abstract (en)
A document sensing apparatus includes voltage generating means (12) for generating a first or second voltage depending on whether or not, respectively, a document is present at a sensing location, and capacitive means (36) for providing a second voltage whose peak value is determined by said second value. Voltage comparison means (30,38,40) compares said first and second voltages and provides an output signal indicative of the presence of a document at the sensing location if said first voltage is less than a predetermined fraction of said second voltage. A microprocessor (44) controls the operation of circuit means (74-1) which provides, as necessary, a charging current to said capacitive means (36) so that while a document is present at the sensing location, said second voltage is prevented from falling by a significant amount, thereby preventing problems occurring if a document remains at the sensing location for a prolonged period due to a feeding irregularity. <IMAGE> <IMAGE>
IPC 1-7
IPC 8 full level
G06K 13/067 (2006.01); G07D 11/00 (2006.01)
CPC (source: EP US)
G06K 13/067 (2013.01 - EP US); G07D 11/0096 (2013.01 - EP US)
Designated contracting state (EPC)
DE FR GB
DOCDB simple family (publication)
US 5055670 A 19911008; CA 2045836 A1 19911229; CA 2045836 C 19940531; DE 69108619 D1 19950511; DE 69108619 T2 19951005; EP 0465028 A2 19920108; EP 0465028 A3 19930324; EP 0465028 B1 19950405; GB 9014407 D0 19900822
DOCDB simple family (application)
US 58392590 A 19900917; CA 2045836 A 19910627; DE 69108619 T 19910612; EP 91305332 A 19910612; GB 9014407 A 19900628